Modes coupling and in-plane/out-of-plane vibration in rain-wind induced vibration of cable
LI Tun1,2; CHEN Zheng-qing1; LI Shou-ying1
1. Wind Engineering Experiment Research Center, Hunan University, Changsha 410082, China;2. Department of Civil Engineering, Guangxi University of Technology, Liuzhou 545006, China
Abstract： Assuming the interactions between the cable surface and the rivulet as Coulomb and linear viscous damping forces, the in-plane/out-of-plane vibration model of rain-wind-induced vibration of continuous elastic cable with the moving rivulet was formulated. Differential equations of motion expressed with in-plane and out-of-plane modes of cable were obtained through modes decoupling method. S19 cable of Dongting Lake Bridge was analyzed using this model. It is shown that rain-wind-induced vibration of cable includes several modes which coupling and transforming mutually. The in-plane-vibration and the out-of-plane-vibration are occurred at the same time and the in-plane-vibration occupies dominant position generally. Vibration locus of cable’s section is an inclined ellipse or several inclined ellipsis which interlaced each other. Wind velocity has an important effect on vibration inclination angle of cable. The location of the maximum amplitude is changed with different vibration modes.
2012, Vol. 31 
